E. Pepe | Searcharxiv

arXiv2026

The effects of yields from binary massive stars as functions of metallicity

Massive stars in binary systems that undergo mass transfer during their lifetime have a different evolution from that of single stars, possibly affecting their chemical yields. While massive stars produce most of the metals in the Universe, only few studies have investigated the effects of massive binary stars on the chemical evolution of the Milky Way. Following the most recent studies on massive binary-stripped star yields as functions of metallicity, we aim at improving previous results based on single-metallicity model grids. Here, by adopting a detailed model of chemical evolution for our Galaxy, we compute the evolution of 22 chemical species including C, N, O, $\alpha$-elements and Fe-peak elements, adopting novel prescriptions for single and binary massive star yields. Our main results can be summarised as follows: (i) consistently with previous predictions, we observe very small differences in both the predicted solar abundances and [X/Fe] vs [Fe/H] relations even when including massive binary yields depending on metallicity; (ii) when adopting the new set of stellar yields for massive single stars, as computed by Farmer et al. (2023), we are able to reproduce both the K solar abundance as well as the [K/Fe] vs [Fe/H] relation, without invoking ad hoc assumptions on nucleosynthesis prescriptions; (iii) our model adopting Farmer's yields both for single and binary massive stars is able to better reproduce the [X/Fe] versus [Fe/H] relation for both Mg and Ca, as compared with standard nucleosynthetic yields adopted in chemical evolution models; iv) we find that no models can well reproduce the [C/Fe] and [Ti/Fe] vs [Fe/H] when adopting the new yields as functions of metallicity.

astro-ph.GA↗

arXiv2024

Yields from massive stars in binaries. Chemical evolution of the Milky Way disk

A large fraction of massive stars in the Galaxy reside in binary systems and their evolution is different from that of single stars. The yields of massive stars, which are the main responsible for the production of metals, can be therefore affected by the binary nature of the systems. Recently, Farmer et al. (2023) computed new grids of yields for single and binary-stripped massive stars with solar chemical composition. The main purpose of this paper is to test these yields on the chemical evolution of Galactic stars. To do that, we adopt well-tested chemical evolution models for the Milky Way disk, implementing both yields for single and binary-stripped massive stars. In particular, we assume different percentages of massive binary systems within the initial mass function. We compute the evolution of 22 chemical species starting from $^{4}$He to $^{64}$Zn. Our main results can be summarized as follows: i) when adopting the yields of Farmer et al. (2023), large differences are found relative to the predicted solar abundances by chemical evolution models adopting "standard" massive star yields from the literature for $^{12}$C, $^{14}$N, $^{24}$Mg, $^{39}$K, $^{40}$Ca, $^{55}$Mn and $^{59}$Co. Generally, the yields for single stars reproduce slightly better the observed solar abundances, although for several elements a large fraction of binaries helps in reproducing the observations; ii) different fractions of massive binaries (from 50% to 100%) produce negligible differences in the predicted solar abundances, whereas the differences are more marked between models with and without binary-stripped stellar yields; iii) for the [X/Fe] vs. [Fe/H] relations, the yields including massive stars in binaries produce the best results for $^{52}$Cr, while for $^{12}$C, $^{39}$K, $^{40}$Ca and $^{24}$Mg the best results are obtained with Farmer's yields with no binaries.

astro-ph.GA↗